Electrical relay



Dec. 17, 1963 B. VAN ZYL ELECTRICAL RELAY Filed Nov. 5, 1960 INVENTOR Barnard M1 2 2 BY a fig

ATTORNEYS United States Patent 3,114,808 ELECTRIICAL RELAY Bernard van Zyl, Lancaster, Pa., assignor to Hamilton Watch Company, Lancaster, Pa., a corporation of Pennsylvania Filed Nov. 3, 1960, Ser. No. 67,660 7 Claims. (Cl. Nil-87) This invention relates to relays and more particularly to relays which maintain a consistent contact pressure in vibration environments.

In many of the applications in which electrical relays are used, environmental factors have a detrimental effect on their proper operation. One such environmental factor is vibration. lln many of the electrical circuits used in airplanes, for example, relays are subject to such severe vibration as to render them incapable of maintaini'ng consistent contact pressure. The erratic contact pressure thus resulting causes the relay to exhibit what is termed contact noise. This contact noise often interferes with the proper functioning of the various circuits.

According to the present invention, it has now been found possible to provide a relay which is immune to contact noise caused by varying contact pressure due to vibration. The present invention relies on a combination of spring forces and electromagnetic forces to provide a constant contact pressure and is both simple and cornpact in construction.

It is therefore a primary object of the present invention to provide a relay having a constant contact pressure.

It is also an object of this invention to provide a relay which is not aversely affected by vibration.

It is another object of the present invention to provide a relay utilizing both spring and electromagnetic forces to maintain a constant contact pressure. I

These and further objects and advantages of the invention will become more apparent by reference to the following specification and claims and appended drawings wherein:

FIGURE 1 is a partial schematic view of one embodiment of the present invention; and

FIGURE 2 is a partial schematic view of another embodiment of the present invention.

Referring now to FIGURE 1, a relay generally indicated at 1 is provided with a coil 2 having an armature 4 which has a vertical portion 3 and a horizontal portion 7. The horizontal portion 7 is mounted for rotation about a shaft 6 suitably mounted in a housing 9. The magnetic field created when the coil is energized causes the vertical portion 3 and thus the armature 4 to rotate about the shaft 6 in a counterclockwise direction. A spring 8 is biased against the force created by an energization of the coil 2 and serves to keep the armature in a first of two possible positions when the coil is not energized.

The horizontal portion 7 of the armature has attached thereto a slender metal rod 10. This rod can be attached in any suitable manner, such as by welding or soldering. The other end of the rod 10 is surrounded by an insulator 12 which also surrounds one end of a conducting rod 14. A wedge-shaped contact 16 is carried by the other end of the rod 14 and is likewise constructed of a good conducting material. A wire 18 is fastened to the rod 14 in any known manner such as by solder 20. The other end of the wire 18 is connected to a terminal 22 in any known manner such as by solder 24. The terminal 22 acts as the commen terminal in the present embodiment. The common terminal 22 is mounted in a base 26 by means of an insulator 28.

Also mounted in the base 26, by means of insulators 3,114,808 Patented Dec. 17, 1963 34 and 36, are terminal pins 30 and '32. The terminal 30 has a horizontal portion 38 and is so constructed that this horizontal portion acts as a cantilever spring and forces a gold ball 40 mounted on its outer end against the wedge 16. The terminal 30 thus acts as the normally closed terminal of the relay. The terminal 32 is similar in construction to the terminal 30 and has a horizontal portion 42 which carries a gold ball 44 on its outer end. This horizontal portion 42 is constructed so that it acts as a cantilever spring and tends to push the ball 44 upwards. This terminal acts as the normally open terminal of the relay.

In the operation of the relay just described, the spring 8 normally keeps the armature 4 in its extreme clockwise position. -In this position, the arm 10', insulator 12 and arm 14 force the wedge 16 against the ball 40. The cantilever spring action of the horizontal portion 38 or the terminal 3% acts to force the ball 46 upwards against the wedge 16, thus maintaining pressure of the ball against the wedge. These two forces acting on the ball and wedge keep the contact pressure between them at a sufiicient level so that no contact noise will occur even if the relay is subjected to rather severe vibrations.

When coil 2 is energized, the armature 4 rotates against the force of spring 8. As the armature rotates, it cartries with it the rod 10, insulator 12 and rod 14 until the wedge 16 is pushed firmly against the ball 44. The armature and coil are so arranged that when the coil is energized, the armature never rotates to a fixed stop but is constantly driving the wedge 16 against the ball 44. Since the horizontal portion 42 of the terminal 52 is constantly urging the ball 44 upwards against the wedge, the cont-act pressure is kept at a level which eliminates any contact noise even in a vibration environment.

Referring now to FIGURE 2, there is shown a modification of the relay shown in FIGURE 1. This relay is similar in structure to that shown in FIGURE 1 but provides anumber of make and break contacts for controlling a number of circuits. In this figure, similar parts have the same reference numerals used in FIGURE 1.

A coil 2 drives an armature '4 mounted on a shaft 6 and biased by a spring 8 as in FIGURE 1. The hori zontal portion 7 of the armature, however, carries a plurality of rods 46, 82 and 114 instead of the single rod carried by the armature of the relay shown in FIGURE 1.

The rod 46 is attached at its other end to an insulator 48 which also carries a conductive rod 50 on which is mounted a wedge 52 made of a good conducting material. A wire 54 is attached to the rod 50 by solder 56 at one end and is attached at the other end to a terminal pin 58 by solder 60. The terminal pin 58 is mounted in a base '62 and insulated therefrom by an insulator 64. Also mounted in the base 62 are a pair of terminals 66 and 68 which are similarly insulated by insulators 70 and 72. The terminals 66 and 68 have horizontal cantilever spring portions 74 and 78 respectively which carry gold balls 76 and 80 on their outer arms. These gold balls interact with the wedge 52 in the same manner as described in connection with the relay of FIGURE 1.

Ina similar fashion, the rod 82 carries an insulator 84 to which is aifixed a conductive rod 86. The rod 86' carries a conductive wedge 88. A wire 90 is attached at one end to the rod 86 by solder 92 and at the other end to a terminal 94 by solder 96. The terminal 94 is mounted in the base 62 by means of an insulator 95. The wedge 88 cooperates with gold balls 108 and 112 which are mounted on cantilever arms 106 and of terminals 98 and 100. These terminals are mounted in the base 62 by insulators 102 and 194.

The third rod 114 carries an insulator 116 in the other end of which is mounted a conductive rod 118. The

a rod 118 carries at its other end a wedge 12% constructed of a highly conductive material. A wire 122 is soldered to the rod 118 at 124 and is attached to a terminal 126 by solder 128. The terminal 126 is mounted in the base 62 and insulated therefrom by an insulator 127. Terminals 130 and 132 have cantilever spring portions 138 and 142 which carry at their outermost extremities gold balls 140 and 144 respectively. These gold balls cooperate with the wedge 12% in a manner described above. The terminals 130 and 132 are mounted in the base 62 and insulated therefrom by insulators 134 and 135.

Although three single pole double throw switches are shown mounted on the base 62 in FIGURE 2, it is to be understood that any desired number could be so mounted. The various terminals are preferably positioned with respect to the base so that a unitary structure is formed that can be plugged into a socket, thus controlling a number of individual circuits. As is the case in FIGURE 1, all of the switches are controlled by the movement of the armature 4 under the influence of the coil 2. The switches are normally biased in their clockwise position by the spring 8 and the contact pressure is kept constant by action of this spring and the cantilever springs of the various terminals. When the coil is energized, the armature rotates carrying the wedges against the gold balls carried on the other cantilever spring arms on the other terminals. The interaction of these forces keeps the contact pressure effectively constant as explained in connection with FIGURE 1.

Although single pole double throw switches are shown in the several embodiments, it is to be understood that any switching configuration could be used as desired. It should also be apparent that any of the terminals can perform any desired function in a particular circuit. The use of gold is preferred for the contact balls used in the disclosed relay, but any soft material possessing high conductivity could be used. It is also not necessary that the movable contact be formed in the shape of a wedge so long as the cooperating contact surfaces engage in a plane other than the plane in which the movable contact moves and are biased together along a line substantially normal to the plane containing the contact surfaces. As an example, spheres could be used for all contacts or the stationary contacts might be wedge shaped while the movable contact is a sphere. With this arrangement, vibration of the movable contact along its established path of movement does not cause chatter or discontinuity of the connection. Indeed, a wiping action is created which insures clean contact surfaces.

By the apparatus described above, it can be seen that the deleterious effects of vibration on relays can be eliminated. By the use of a combination of cantilever spring forces, return spring forces and electromagnet forces, the contact pressure in a relay or series of relays can be kept at a value high enough to avoid any possibility of contact noise. The structure described is simple and compact and can easily be formed to be plugged into any particular circuit or circuits.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In an electrical relay, a coil having a core, housing means supporting said coil, shaft means mounted in said housing at substantially a right angle to said core, an armature comprising a vertical and a horizontal portion, said horizontal portion being mounted for rotation about said shaft, said vertical portion being positioned so as to rotate said horizontal portion when said coil is energized, spring means mounted on said housing and bearing against said horizontal portion for biasing said armature against rotation, contact means mounted on said horizontal portion of said armature, and fixed contact means mounted on a base whereby movement of said armature by energizing said coil brings said contact means carried by said horizontal portion of said armature into contact with said fixed contact means.

2. The apparatus of claim 1 wherein said contact means carried by said horizontal portion of said armature comprises rod means fixedly mounted by one end to said horizontal portion, insulating means carried on the other end of said rod means, and a contact mounted in said insulating means, said contact being substantially wedge-shaped for riding upon said fixed contact means when said relay operates.

3. The apparatus of claim 2 wherein said fixed contacts comprise a cantilever spring supporting a spherically shaped contact surface whereby said wedge-shaped contact is subjected to a resilient pressure exerted by said fixed contact when said relay operates.

4. A relay comprising a coil wound around a core, housing means supporting said coil, shaft means mounted in said housing means at substantially a right angle to said core and on an axis intersecting the axis of said core, an armature mounted for rotational movement on said shaft in a first direction upon energization of said coil, said armature having a horizontal portion pivoted to said shaft and a vertical portion which is attracted by said core to impart rotational movement to said horizontal portion, first contact means carried by said horizontal part of said armature, second contact means resiliently mounted on said housing means so that motion of said second contact means in a second direction is resiliently resisted, said first direction and said second direction being different, said first contact means engaging said second contact means upon energization of said coil whereby said vertical portion of said armature is attracted to said core, said contact means being so shaped that said engagement causes said second contact means to move in said second direction as said first contact means moves in said first different direction, and spring means on said housing means engaging said armature and biasing it toward a position where said contact means are not in engagement.

5. A relay as set out in claim 4 wherein said first direction of movement lies substantially in a plane which is substantially perpendicular to said second direction of movement.

6. A relay as set out in claim 4 wherein one of said contact means has a surface at least a portion of which is substantially spherical, and the other contact means has a surface at least a portion of which is wedge shaped, said spherical and wedge shaped portions being mounted for relative sliding motion to create a pressure between said surfaces as said contact means are moved in different directions.

7. A relay as set out in claim 5 wherein bne of said contact means has a surface at least a portion of which is substantially spherical, and the other contact means has a surface at least a portion of which is wedge shaped, said spherical and wedge shaped portions being mounted for relative sliding motion to create a pressure between said surfaces as said contact means are moved in different directions, said second contact means being carried by a cantilever spring which supplies said resilient resistance.

References Cited in the file of this patent UNITED STATES PATENTS 1,354,181 Gazda Sept. 28, 1920 1,461,825 Lalonde July 17, 1923 2,413,148 Martin Dec. 24, 1946 2,559,199 Perkins July 3, 1951 (fither references on following page) 6 Kramer Aug. 11, 1959 Wharton Get. 27, 1959 Brown et a1 Feb. 23, 1960 Richert Oct. 4, 1960 FOREIGN PATENTS Great Britain Jan. 7, 1938 Great Britain Sept. 14, 1955 

1. IN AN ELECTRICAL RELAY, A COIL HAVING A CORE, HOUSING MEANS SUPPORTING SAID COIL, SHAFT MEANS MOUNTED IN SAID HOUSING AT SUBSTANTIALLY A RIGHT ANGLE TO SAID CORE, AN ARMATURE COMPRISING A VERTICAL AND A HORIZONTAL PORTION, SAID HORIZONTAL PORTION BEING MOUNTED FOR ROTATION ABOUT SAID SHAFT, SAID VERTICAL PORTION BEING POSITIONED SO AS TO ROTATE SAID HORIZONTAL PORTION WHEN SAID COIL IS ENERGIZED, SPRING MEANS MOUNTED ON SAID HOUSING AND BEARING AGAINST SAID HORIZONTAL PORTION FOR BIASING SAID ARMATURE AGAINST ROTATION, CONTACT MEANS MOUNTED ON SAID HORIZONTAL PORTION OF SAID ARMATURE, AND FIXED CONTACT MEANS MOUNTED ON A BASE WHEREBY MOVEMENT OF SAID ARMATURE BY ENERGIZING SAID COIL BRINGS SAID CONTACT MEANS CARRIED BY SAID HORIZONTAL PORTION OF SAID ARMATURE INTO CONTACT WITH SAID FIXED CONTACT MEANS. 